Standard Triplet with 15 lcd Throw?

physics are physics!

If he really is projecting a 15" LCD to make an 8' diagonal image from a 12' throw, then he has around a 500 mm fl projection lens. I suspect your distance estimates are a bit off, and he really has one of the standard 480 mm fl triplets.

This is why people make long-throw projectors: So you don't have to struggle to see around the projector box that is sitting in the middle of the room.
looks like a smaller lens to me

Maybe it is a process lens. It looks like many of them I have seen. They are always pretty short, since they have such wide FOV.

But there really is no way to escape the physical laws: If he has those sizes and distances, his lens fl is around 500 mm. Why don't you see if you can ask him by email?